Early and late preterm birth rates in participants adherent to randomly assigned high dose docosahexaenoic acid (DHA) supplementation in pregnancy.

BACKGROUND: Intention-to-treat analyses do not address adherence. Per protocol analyses treat nonadherence as a protocol deviation and assess if the intervention is effective if followed. OBJECTIVE: To determine the rate of early preterm birth (EPTB, <34 weeks gestation) and preterm birth (PTB, <37 weeks gestation) in participants who adhered to a randomly assigned docosahexaenoic acid (DHA) dose of 1000 mg/day. STUDY DESIGN: Eleven hundred women with a singleton pregnancy were enrolled before 20-weeks' gestation, provided a capsule with 200 mg/day DHA and randomly assigned to two additional capsules containing a placebo or 800 mg of DHA. In the Bayesian Adaptive Design, new randomization schedules were determined at prespecified intervals. In each randomization, the group with the most EPTB was assigned fewer participants than the other group. Adherence was defined a priori as a postpartum red blood cell phospholipid DHA (RBC-PL-DHA) ≥5.5%.and post hoc as ≥8.0% RBC-PL-DHA, the latter after examination of postpartum RBC-PL-DHA. Bayesian mixture models were fitted for gestational age and dichotomized for EPTB and PTB as a function of baseline RBC-PL-DHA and dose-adherence. Bayesian hierarchical models were also fitted for EPTB by dose adherence and quartiles of baseline RBC-PL-DHA. RESULTS: Adherence to the high dose using both RBC-PL-DHA cut points resulted in less EPTB compared to 200 mg [Bayesian posterior probability (pp) = 0.93 and 0.92, respectively]. For participants in the two lowest quartiles of baseline DHA status, adherence to the higher dose resulted in lower EPTB (≥5.5% RBC-PL-DHA, quartiles 1 and 2, pp = 0.95 and 0.96; ≥8% RBC-PL-DHA, quartiles 1 and 2, pp = 0.94 and 0.95). Using the Bayesian model, EPTB was reduced by 65%, from 3.45% to 1.2%, using both cut points. Adherence also reduced PTB before 35, 36 and 37 weeks using both cut points (pp ≥ 0.95). In general, performance of the nonadherent subgroup mirrored that of participants assigned to 200 mg. CONCLUSION: Adherence to high dose DHA reduced EPTB and PTB. The largest effect of adherence on reducing EPTB was observed in women with low baseline DHA levels. CLINICALTRIALS: gov (NCT02626299).

Docosahexaenoic acid (DHA) intake estimated from a 7-question survey identifies pregnancies most likely to benefit from high-dose DHA supplementation.

BACKGROUND: Two randomized trials found women with low blood docosahexaenoic acid (DHA; an omega 3 fatty acid) had fewer early preterm births (<34 weeks gestation) if they were assigned to high dose DHA supplementation, however, there is currently no capacity for clinicians who care for pregnancies to obtain a blood assessment of DHA. Determining a way to identify women with low DHA intake whose risk could be lowered by high dose DHA supplementation is desired. OBJECTIVE: To determine if assessing DHA intake can identify pregnancies that benefit from high dose DHA supplementation. STUDY DESIGN: This secondary analysis used birth data from 1310 pregnant women who completed a 7-question food frequency questionnaire (DHA-FFQ) at 16.8 ± 2.5 weeks gestation that is validated to assess DHA status. They were then randomly assigned to a standard (200 mg/day) or high dose (800 or 1000 mg/day) DHA supplement for the remainder of pregnancy. Bayesian logistic regressions were fitted for early preterm birth and preterm birth as a function of DHA intake and assigned DHA dose. RESULTS: Participants who consumed less than 150 mg/day DHA prior to 20 weeks' gestation (n = 810/1310, 58.1%) had a lower Bayesian posterior probability (pp) of early preterm birth if they were assigned to high dose DHA supplementation (1.4% vs 3.9%, pp = 0.99). The effect on preterm birth (<37 weeks) was also significant (11.3% vs 14.8%, pp = 0.97). CONCLUSION: The DHA-FFQ can identify pregnancies that will benefit most from high dose DHA supplementation and reduce the risk of preterm birth. The DHA-FFQ is low burden to providers and patients and could be easily implemented in obstetrical practice.

Validation of an abbreviated food frequency questionnaire for estimating DHA intake of pregnant women in the United States.

Docosahexaenoic acid (DHA) intake was estimated in pregnant women between 12- and 20-weeks' gestation using the National Cancer Institute's (NCI) Diet History Questionnaire-II (DHQ-II) and a 7-question screener designed to capture DHA intake (DHA Food Frequency Questionnaire, DHA-FFQ). Results from both methods were compared to red blood cell phospholipid DHA (RBC-DHA) weight percent of total fatty acids. DHA intake from the DHA-FFQ was more highly correlated with RBC-DHA (rs=0.528) than the DHQ-II (rs=0.352). Moreover, the DHA-FFQ allowed us to obtain reliable intake data from 1355 of 1400 participants. The DHQ-II provided reliable intake for only 847 of 1400, because many participants only partially completed it and it was not validated for Hispanic participants. Maternal age, parity, and socioeconomic status (SES) were also significant predictors of RBC-DHA. When included with estimated intake from the DHA-FFQ, the model accounted for 36% of the variation in RBC-DHA.

Utility of a 7- question online screener for DHA intake.

The secondary analyses of two large, recently completed randomized clinical trials of DHA supplementation in pregnancy found that women with a low baseline DHA status benefited from randomization to a higher dose (800 vs 0 and 1000 vs 200 mg/day DHA). To obtain DHA status, it is necessary to obtain a blood sample and conduct an analysis using gas chromatography (GC) or GC-mass spectrometry (GCMS), both barriers to clinics where pregnant women receive advice on nutrition. Participants consuming less than 150 mg/day of DHA at baseline in our recent trial had a lower risk of early preterm birth and preterm birth when assigned to 1000 vs 200 m/day DHA. DHA intake was determined using a 7-question food frequency questionnaire administered by a trained nutritionist. Because the need for trained personnel to administer the questionnaire would be a barrier to implementing this finding in clinical management of pregnancy, the goal of this study was to determine if an online version of the questionnaire could be validly completed without assistance.

Structural implications of fenestrated stent graft misalignment.

BACKGROUND: Endovascular aneurysm repair is a minimally-invasive method for the treatment of abdominal aortic aneurysms. For aneurysms that involve the visceral arteries, a custom-made stent graft with fenestrations for the branch arteries is required. The purpose of the current study is to evaluate the structural impact of misaligned fenestrations with respect to luminal patency and proximal aortic neck apposition in an in vitro model. METHODS: A custom apparatus was used to evaluate seven Anaconda and three Zenith fenestrated stent grafts. All stent grafts were evaluated at 10° increments of stent/fenestration misalignment up to 80°. Images were captured at each interval and the luminal cross-sectional area and wall apposition were measured. RESULTS: The Anaconda stent graft, which has an unsupported main body, demonstrated a linear reduction in luminal patency at increasing angles of misalignment (P < 0.0001). Stent/fenestration misalignments of 20° and 80° resulted in decreases in mean luminal patency of 14% and 54% respectively. The Zenith stent graft demonstrated a similar decrease in luminal patency, starting at misalignments of ≥40° (P < 0.0001). However, with stent/fenestration misalignments of ≥30°, apposition between the Zenith stent graft and the simulated aortic neck was compromised suggesting the creation of a type Ia endoleak. CONCLUSIONS: Both the Anaconda and Zenith devices behave adversely at extreme angles of misalignment with luminal narrowing in the Anaconda device and loss of wall apposition in the Zenith device; however, both stent grafts appear to be equivalent at low angles of misalignment.

Psychiatric predictors of surgery non-completion following suitability assessment for bariatric surgery.

BACKGROUND: Bariatric surgery is recognized as a treatment for severe obesity; however, little is known about factors influencing patient surgery non-completion. This study explored the relationship between psychiatric factors and patient non-completion during the pre-bariatric surgery suitability assessment. METHODS: A total of 367 individuals underwent a structured psychiatric interview and were classified as either surgery completers (SC) or surgery non-completers (SNC) if they attended at least one pre-surgery assessment appointment but did not receive surgery. RESULTS: The results showed that in comparison to the SC group, the SNC group had significantly higher rates of overall past Axis I psychiatric disorders (58.1 vs. 46.6 %, p = 0.035), past anxiety disorders (17.4 vs. 9.4 %, p = 0.03), and past substance use disorders (8.7 vs. 3.7 %, p = 0.03). For specific past psychiatric disorders, the SNC group exhibited significantly higher rates of a past post-traumatic stress disorder (PTSD) (5 vs. 1 %, p = 0.029) and past substance dependence disorder (7 vs. 1 %, p = 0.005). Although overall current psychiatric disorders did not significantly differ between groups, the SNC group had significantly higher rates of current PTSD (2 vs. 0 %, p = 0.049) and current generalized anxiety disorder (4 vs. 0 %, p = 0.005). CONCLUSIONS: A past history of an anxiety or substance use disorder may play a role in patients not completing the assessment component of the bariatric surgery process. Additional psychosocial support, such as cognitive behavioral therapy or targeted psychoeducation, may help improve patient completion of the pre-surgery assessment phase.

Naturally occurring R225W mutation of the gene encoding AMP-activated protein kinase (AMPK)gamma(3) results in increased oxidative capacity and glucose uptake in human primary myotubes.

AIMS/HYPOTHESIS: AMP-activated protein kinase (AMPK) has a broad role in the regulation of glucose and lipid metabolism making it a promising target in the treatment of type 2 diabetes mellitus. We therefore sought to characterise for the first time the effects of chronic AMPK activation on skeletal muscle carbohydrate metabolism in carriers of the rare gain-of-function mutation of the gene encoding AMPKgamma(3) subunit, PRKAG3 R225W. METHODS: Aspects of fuel metabolism were studied in vitro in myocytes isolated from vastus lateralis of PRKAG3 R225W carriers and matched control participants. In vivo, muscular strength and fatigue were evaluated by isokinetic dynamometer and surface electromyography, respectively. Glucose uptake in exercising quadriceps was determined using [(18)F]fluorodeoxyglucose and positron emission tomography. RESULTS: Myotubes from PRKAG3 R225W carriers had threefold higher mitochondrial content (p < 0.01) and oxidative capacity, higher leak-dependent respiration (1.6-fold, p < 0.05), higher basal glucose uptake (twofold, p < 0.01) and higher glycogen synthesis rates (twofold, p < 0.05) than control myotubes. They also had higher levels of intracellular glycogen (p < 0.01) and a trend for lower intramuscular triacylglycerol stores. R225W carriers showed remarkable resistance to muscular fatigue and a trend for increased glucose uptake in exercising muscle in vivo. CONCLUSIONS/INTERPRETATION: Through the enhancement of skeletal muscle glucose uptake and increased mitochondrial content, the R225W mutation may significantly enhance exercise performance. These findings are also consistent with the hypothesis that the gamma(3) subunit of AMPK is a promising tissue-specific target for the treatment of type 2 diabetes mellitus, a condition in which glucose uptake and mitochondrial function are impaired.

Increased susceptibility to oxidative damage in post-diabetic human myotubes.

AIMS/HYPOTHESIS: Obesity is an important risk factor for the development of type 2 diabetes, but not all obese individuals develop this complication. The clinical signs of type 2 diabetes can often be reversed with weight loss; however, it is unknown whether the skeletal muscle oxidative stress associated with type 2 diabetes remains after weight loss. We hypothesised that chronic exposure to high glucose and insulin would re-elicit impaired metabolism in primary myotubes from patients with a history of type 2 diabetes. METHODS: Obese participants with or without type 2 diabetes completed a standardised weight loss protocol, following which all participants were euglycaemic and had similar indices of insulin sensitivity. Satellite cells were isolated from muscle biopsies and differentiated under low or high glucose and insulin conditions (HGI). RESULTS: Cells from participants with no history of type 2 diabetes showed robust increases in mitochondrial content, citrate synthase and cytochrome c oxidase activities when exposed to HGI. This increase in oxidative capacity was absent in cells from patients with a history of type 2 diabetes. High glucose and insulin caused increased oxidative damage in cells from the latter, despite higher superoxide dismutase expression. Cells from patients with a history of type 2 diabetes were unable to decrease mitochondrial membrane potential in response to HGI, potentially due to lower levels of uncoupling protein-3. CONCLUSIONS/INTERPRETATION: This is the first report to note that primary myotubes from patients with a history of type 2 diabetes are unable to adapt to a hyperglycaemic-hyperinsulinaemic challenge. We have demonstrated that impaired mitochondrial biogenesis and an inability to manage oxidative stress define a muscle phenotype at risk of obesity-associated type 2 diabetes.

Interface pressure measurements: visual interpretation of pressure maps with MS clients.

PURPOSE: Pressure mapping systems provide useful information for pressure care assessment. Healthcare professionals tend to rely upon their colour-coded pressure maps to assist clinical decision-making, based on ranking these from best to worst pressure distribution. The current study investigated whether such ranking is an appropriate method of assessment when compared to use of the numerical output of average and maximum pressure values (mmHg), yielded by the system. METHOD: This community-based correlational study involved 27 multiple sclerosis clients (15 wheelchair users; 12 non-wheelchair users). Pressure maps were recorded on each participant's current seating surface and on six pressure reducing cushions, using the Force Sensing Array pressure mapping system. Outcome measures included (1) rank order of pressure maps based on visual interpretation by two occupational therapists, (2) average pressure (mmHg) and (3) maximum pressure (mmHg). Visual ranking of the colour-coded pressure maps was correlated with average and maximum pressure values for each map. RESULTS: Correlations between visual ranking of maps and maximum pressures were high for six out of seven surfaces (p < 0.05) for non-wheelchair users; however, they were much less between average pressures and visual interpretation for the same cohort. Similarly, correlations between visual ranking of maps and average pressures for wheelchair users was minimal and was only noted as being high (p < 0.05) on two surfaces when considering maximum pressures and visual interpretation. CONCLUSIONS: This study contests the usefulness of the visual ranking of pressure maps in interpreting interface pressures with MS clients, especially with wheelchair users. Visual interpretation of pressure maps by clinicians may be useful in eliminating inappropriate support surfaces from a selection, or those that display easily identifiable 'extremes' of pressure values. Clinicians need to incorporate and interpret the numerical data as well as pressure maps when conducting their assessment and making provision.

Cellular and subcellular compartmentation of Ni in the Eurasian serpentine plants Alyssum bracteatum, Alyssum murale (Brassicaceae) and Cleome heratensis (Capparaceae).

This study investigated the cellular and subcellular compartmentation of Ni in the Eurasian serpentine species Alyssum murale, Alyssum bracteatum and Cleome heratensis and a non-serpentine population of A. murale (as a control) grown in hydroponic culture. Plant growth responses and Ni uptake clearly revealed the higher Ni tolerance of serpentine plants than the non-serpentine plants. Serpentine A. murale and A. bracteatum grew better at elevated (0.01 mM) Ni in the nutrient solution, supporting the view that the Ni hyperaccumulators have a higher requirement for Ni than normal plants. Low shoot Ni content of C. heratensis in response to the high Ni treatments indicated that this species employs an avoidance strategy for Ni tolerance. Energy-dispersive X-ray microanalysis showed that Ni was highly concentrated in the cell walls and cell lumen, most likely the vacuoles, of leaf epidermis of A. murale and A. bracteatum rather than in the mesophyll cells. EDX spectra from leaves of the non-serpentine A. murale suggested that Ni accumulated in both epidermal and mesophyll cells but not in the epidermal cell walls. Growth reduction and Ni toxicity in plants of the non-serpentine A. murale could be due to accumulation of Ni in the lumen of leaf mesophyll cells. Our data suggest that cellular and subcellular compartmentation are both possible mechanisms for Ni tolerance employed by the serpentine A. murale and A. bracteatum.

Hammocking: the effect of cushion covers on interface pressure measurements.

PURPOSE: To investigate the effects of the cushion covers on interface pressure measurements using pressure mapping technology. METHODS: Sixty-one healthy participants were recruited for a laboratory-based study using a single group design. Participants were pressure mapped on a visco-elastic foam cushion and a foam and fluid pack cushion with their covers on and with their covers removed. An air-filled cushion was tested with two different types of covers, an incontinence cover and a 'Comfair' cover. Average and maximum pressures recorded at 6 mins by the Force Sensing Array pressure mapping system were used for statistical analysis. RESULTS: There were no significant differences in maximum pressures for the three cushions tested with their covers on or with their covers removed. The cushion with the foam base and fluid pack did not demonstrate any significant differences in average pressure with the cover on or with the cover removed. However, the visco-elastic foam cushion showed significantly lower average pressures with the cover on (p=0.019). The air-filled cushion showed lower average pressures with the incontinence cover on, when compared to the Comfair cover (p=0.029). CONCLUSION: Contrary to the belief that the process of hammocking may create surface tension within the cushion covers, which in turn may adversely affect the cushions ability to reduce interface pressure, the cushions tested in the current study did not show significantly lower interface pressure measurements with the covers removed. Therefore the covers did not adversely affect the cushion's ability to reduce interface pressure. The findings of this study require verification with disabled clients.

An investigation of the impact of the Force Sensing Array pressure mapping system on the clinical judgement of occupational therapists.

OBJECTIVES: To examine the impact of pressure mapping technology on the clinical decisions of occupational therapists and to examine the role of the Braden Scale in assisting with the selection of pressure-reducing cushions. DESIGN: Case studies. SETTING: Community. SUBJECTS: Forty clients. INTERVENTIONS: Clients were pressure mapped on their current seating surface and on four pre-selected cushions by the principal researcher. An occupational therapist completed the Braden Scale and a decision tree to assist in recommending a suitable pressure-reducing cushion. MAIN OUTCOME MEASURES: Interface pressure maps, Braden Scale, and the cushion recommended, using a decision tree to guide clinical judgement. RESULTS: Thirty per cent (12) of the 40 cushions recommended were changed when the pressure maps from the Force Sensing Array (FSA) system were viewed. In 70% (26) of cases, the maps supported the cushion recommended. In 25% (10) of the cases, the maps showed that the client's current seating surface was unsuitable. After viewing the pressure maps, a surface other than the client's current surface was recommended in 47% (19) of the cases. There was a lack of agreement between the risk level of the clients as identified by the Braden Scale score, and the risk level of the clients as identified by the occupational therapist using a decision tree and the FSA maps. CONCLUSION: Pressure mapping technology has a positive impact on clinical decisions regarding the provision of pressure-reducing cushions. Future research should examine the predictive validity of this technology. The Braden Scale may underpredict the risk level of the clients.

Mutations in folP associated with elevated sulfonamide MICs for Neisseria meningitidis clinical isolates from five continents.

Sulfonamide resistance in meningococci is associated with mutations in the chromosomal gene folP, which encodes dihydropteroate synthase. Several mutations associated with resistance have been previously described, including amino acid substitutions at codons 31 and 194, a glycine-serine insertion at codons 195 and 196, and, recently, an additional mutation at nucleotide 682 (C682A). In this study, sulfisoxazole MICs were determined for 424 geographically diverse clinical isolates of Neisseria meningitidis, including all major subtypes. A subset of 134 isolates with MICs ranging from 0.5 to >64 microg/ml were assayed for the C682A mutation by real-time PCR, and 25 isolates were selected for folP gene sequencing. All isolates for which the sulfisoxazole MIC was >/=8 possessed the C682A mutation by real-time PCR or folP sequencing, and 34 of 35 isolates with a MIC of /=4, 15 possessed previously described mutations, including 10 at codon 31, 1 at codon 194, and 4 with the 2-amino-acid insertion codons 195 and 196; all 16 possessed the C682A mutation. The C682A mutation predicted elevated sulfonamides MICs for a large number of geographically diverse clinical isolates of meningococci. Detection of this mutation by real-time PCR or other methods may allow more wide-scale detection of meningococcal isolates with for which the sulfonamide MICs are elevated without resorting to multiple assays or folP gene sequencing, providing a simple, high-throughput screening method for use in public health and epidemiologic settings.

Detection of resistance to gatifloxacin and moxifloxacin in Streptococcus pneumoniae with the VITEK 2 instrument.

A group of 72 pneumococcal isolates resistant or intermediate to levofloxacin and 124 pneumococcal isolates susceptible to fluoroquinolones were tested by the VITEK 2 instrument using investigational test cards and by a broth microdilution reference method. The VITEK 2 instrument performed well, detecting 52 of 60 (86.7%) gatifloxacin-resistant isolates and 22 of 23 moxifloxacin-resistant isolates, and did not falsely classify any susceptible isolates as resistant.

Detection of inducible clindamycin resistance of staphylococci in conjunction with performance of automated broth susceptibility testing.

This study has shown that inducible clindamycin resistance in staphylococci can be detected by disk testing on sheep blood agar inoculum purity plates used with the bioMerieux VITEK 2. Tests of 150 erythromycin-resistant isolates correlated with standard D-zone tests on Mueller-Hinton agar and with PCR for erm(A), erm(C), and msr(A).

Practical disk diffusion method for detection of inducible clindamycin resistance in Staphylococcus aureus and coagulase-negative staphylococci.

Resistance to macrolides in staphylococci may be due to active efflux (encoded by msrA) or ribosomal target modification (macrolide-lincosamide-streptogramin B [MLSB] resistance; usually encoded by ermA or ermC). MLSB resistance is either constitutive or inducible following exposure to a macrolide. Induction tests utilize closely approximated erythromycin and clindamycin disks; the flattening of the clindamycin zone adjacent to the erythromycin disk indicates inducible MLSB resistance. The present study reassessed the reliability of placing erythromycin and clindamycin disks in adjacent positions (26 to 28 mm apart) in a standard disk dispenser, compared to distances of 15 or 20 mm. A group of 130 clinical isolates of Staphylococcus aureus and 100 isolates of erythromycin-resistant coagulase-negative staphylococci (CNS) were examined by disk approximation; all CNS isolates and a subset of S. aureus isolates were examined by PCR for ermA, ermC, and msrA. Of 114 erythromycin-resistant S. aureus isolates, 39 demonstrated constitutive resistance to clindamycin, while 33 showed inducible resistance by disk approximation at all three distances. Only one isolate failed to clearly demonstrate induction at 26 mm. Of 82 erythromycin-resistant CNS isolates that contained ermA or ermC, 57 demonstrated constitutive clindamycin resistance, and 25 demonstrated inducible resistance, at 20 and 26 mm. None of the 42 S. aureus isolates or 18 CNS isolates containing only msrA and none of the erythromycin-susceptible isolates yielded positive disk approximation tests. Simple placement of erythromycin and clindamycin disks at a distance achieved with a standard disk dispenser allowed detection of 97% of S. aureus strains and 100% of CNS strains with inducible MLSB resistance in this study.

Identification of a 41 kDa protein embedded in the biosilica of scales and bristles isolated from Mallomonas splendens (Synurophyceae, Ochrophyta).

Cells of the photosynthetic protist Mallomonas splendens (Synurophyceae, Ochrophyta) are encased within a highly patterned wall or scale case that consists of silicified scales and bristles. In an effort to understand the mechanisms that unicellular protists utilize to produce elaborate, mineralized structures of great complexity and hierarchical structure, we identified and characterized a 41 kDa protein from purified scales/bristles isolated from M. splendens (SP41 for Scale Protein of 41 kDa). A cDNA encoding this protein was isolated and sequence analysis indicated that it is a novel protein. Polyclonal antibodies were generated against bacterially expressed SP41 and used to localize the protein throughout scale and bristle morphogenesis. Immunoelectron microscopy confirmed the biochemical data that SP41 is a component of mature scales and bristles, the protein localizing to silicified components of the purified extracellular matrix. During scale and bristle biogenesis within the cell, SP41 is deposited into a specialized Silica Deposition Vesicle (SDV) concomitant with silica deposition, a highly regulated event during scale and bristle formation. These results argue for SP41 playing a role in morphogenesis and/or silicification within the SDV during scale and bristle biogenesis.

The application of atomic force microscopy to topographical studies and force measurements on the secreted adhesive of the green alga Enteromorpha.

Atomic force microscopy (AFM) enables the topographical structure of cells and biological materials to be resolved under natural (physiological) conditions, without fixation and dehydration artefacts associated with imaging methods in vacuo. It also provides a means of measuring interaction forces and the mechanical properties of biomaterials. In the present study, AFM has been applied for the first time to the study of the mechanical properties of a natural adhesive produced by a green plant cell. Swimming spores of the green alga Enteromorpha linza (L.) J. Ag. (7-10 microm) secrete an adhesive glycoprotein which provides firm anchorage to the substratum. Imaging of the adhesive in its hydrated state revealed a swollen gel-like pad, approximately 1 microm thick, surrounding the spore body. Force measurements revealed that freshly released adhesive has an adhesion strength of 173 +/- 1.7 mN m(-1) (mean +/- SE; n=90) with a maximum value for a single adhesion force curve of 458 mN m(-1). The adhesive had a compressibility (equivalent to Young's modulus) of 0.54 x 10(6) +/- 0.05 x 10(6) N m-2 (mean +/- SE; n=30). Within minutes of release the adhesive underwent a progressive 'curing' process with a 65% reduction in mean adhesive strength within an hour of settlement, which was also reflected in a reduction in the average length of the adhesive polymer strands (polymer extension) and a 10-fold increase in Young's modulus. Measurements on the spore surface itself revealed considerably lower adhesion-strength values but higher polymer-extension values than the adhesive pad, which may reflect the deposition of different polymers on this surface as a new cell wall is formed. The study demonstrates the value of AFM to the imaging of plant cells in the absence of fixation and dehydration artefacts and to the characterisation of the mechanical properties of plant glycoproteins that have potential utility as adhesives.